Definition: Small indentations in the nail.
Causes: Most commonly observed in psoriasis, especially psoriatic arthritis. Can also be seen in alopecia areata.
Examination: A small amount of pitting in nails can be idiopathic and of no clinical importance. Nail pitting can be a key sign of psoriatic arthritis with little skin involvement observable. Observe nails of both hands carefully for ‘sausage’ finger and nail dystrophy (pitting and onchylysis).